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Appendix L


Let condenser heat go to boiler, and thence to engine; let all
expansion heat be abstracted by engine ; and let the total, together
with remaining heat in storage chamber, be used to compress the
gas; then

From storage chamber......Heat = N -. ELP

    condenser and jacket        =       Kp
,,    expansion cylinder...    ,,    =       Kv

Total-  N + KV

which is the same as (i), or the cycle is complete, and the action*
(if without loss) would go on for ever.

Taking values for Kp and Kv and N as normal heat; the-
deficiency in N after condensation is represented by KP-KV =
53'2, and a further deficiency, shewn by Kv=i3o, occurs during;
expansion, the heat abstractions, being therefore 29 per cent, and
71 per cent, of the total abstractions, respectively. If the drop-
be less than the rise of temperature, the condenser will abstract,
a larger proportion, and if the condenser could take its heat at
constant volume, the expansion would do the whole work of heat
abstraction, for then the condenser abstraction would equal the-
compression supply. The condenser water goes partly to feed
the boiler, and partly to heat work-rooms, &c.

Fig. 759 is a section through the air cylinders, whose pistons,
are connected to the engine crank-shaft.    A, the   compression.


cylinder, receives air from the storage chamber, through E, which,
after compression escapes by F to the condenser. Thence it
re-appears, cooled to 60 or 70, and entering the expansion,
cylinder D by passage G, the piston moves upward. The air
volume having shrunk by cooling, cylinder D is much smaller